Apparatus for and method of sealing the ends of wound rolls of sheet material



March 9, 1965 o. H. BESSERDICH 7 3,172,512

APPARATUS FOR AND METHOD OF SEALING THE ENDS OF WOUND ROLLS OF SHEETMATERIAL 2 Sheets-Sheet 1 Filed June 25", 1962 INVENTOR ORRIN BESSERDIOHATTORNEY March 9, 1965 o. H. BESSERDICH 3, 7

APPARATUS FOR AND METHOD OF SEALING THE ENDS 0F WOUND ROLLS 0F SHEETMATERIAL Filed June 25, 1962 2 Sheets-Sheet 2 N m 9\ E8 F 8 ORRINBESSERDICl-l B Aw 2% W fi ATTORNEY United dimes Patent Cfilice 3,172,612APPARATUS FQR AND METHOD ()F SEALING THE ENDS 9F WQUND RQLLS F SHEETMATEREAL Orrin H. Besserdich, Green Bay, Wis., assignor to FMCCorporation, San Jose, Calif., a corporation of Delaware Filed lune 25,1962, Ser. No. 204,981 13 Claims. (Cl. 242-56) This invention relates toreeling and winding, and pertains particularly to the art of convertinga continuous web of sheet material into small rolls suitable formarketing, as paper towelling, toilet tissue and the like.

One of the problems confronting the paper converting industry arisesfrom the tendency for completed rolls of paper, such as toilet tissueand paper towelling, to unwind and thus to present loose ends, or tails,which are not only wasteful and detract from the attractive appearanceof the rolls to such an extent that their marketability is impaired, butwhich also interfere with in-plant handling of the rolls. Whereasvarious methods are currently employed to fasten the roll tails to therolls, thus to prevent unwinding, none has proved to be entirelysatisfactory.

For example, it has been attempted to fasten the tails by means of glueor a similar cementitious bonding agent. This however, tends to stainthe paper, particularly colored tissue, thereby imparting anunattractive appearance to the roll. Glue soaks through several plies,or layers, of the wound roll, so that unless the glue is self-releasingand is effective only for a limited time after application, the gluedroll is difiicult to unwind without tearing and wasting part of theroll. lue and similar bonding agents are ditlicult to apply accuratelyin a preselected area to paper moving at high linear speed, onedisadvantage of which is that if the roll is provided with a pull tab,it must be clear across the full face of the roll, which permits the endof the strip to foldback, permits the loose end to become torn andshredded, and generally results in an unattractive roll.

Another attempt to prevent the tails of wound rolls from unwindinginvolves the use of water instead of glue. This, however, is notdependa'oly elfective, tends to soak through and stain several layers,and leaves the paper in a wrinkled condition after drying. It isdifiicult to fasten a roll tail to the roll, even temporarily, unless anexcessive amount of water is used, and moistened rolls tend to adhere toconveyors and other equipment, which causes ditliculty in subsequentin-plant processing of the rolls. Moreover, the use of water results ina messy operation because the excess water mixes with the paper dustwhich is unavoidable in any paper rewinding operation, and creates ahighly humid atmosphere which is conducive to corrosion of adjacentmetal parts.

Securing the end of a rolled strip by embossing avoids most of thedisadvantages inherent in the use of water or glue, but has thedisadvantage that it cannot be performed by automatic machinery. Therequisite accurate positioning and orientation of the roll prior toembossing must be performed manually and, therefore,'is an expensiveoperation inconsistent with modern, high speed operation.

it is an object of the present invention to provide an improved methodof sealing a roll of sheet material to revent unintentional unwinding ofthe roll.

Another object of the invention is to. provide an improved method oftemporarily attaching the end of a rolled sheet or strip to the nextunderlying layer within the roll.

Another object is to provide a method of sealing the tail of a woundroll of sheet material, which involves the use of a bonding agent whichwill not stain the material,

which does not have any deleterious effect upon the ma= terial, which iseasily applied in the precise area desired, and which creates no problemin connection with subse quent processing of the roll. The bonding agentemployed in the performance of the method of this invention is deendablyefiective in bonding the tail to the underlying layer of sheet materialin the roll for an indefinite time, and yet can easily be made torelease the tail when it becomes desirable to unwind part or all of thematerial.

Another object is to provide apparatus for performing the method of theinvention.

Another object of the invention is to provide, in a paper rewindingmachine, apparatus for fastening the ends of the rewound strips to therolls without individual wrapping so as to prevent them from unwindingduring subsequent handling.

Another object is to provide wound roll sealing, or fastening, apparatusadapted to be incorporated in an existing automatic paper rewindingmachine and to operate automatically in synchronism with it while themachine operates at high speed.

Other objects and advantages of the present invention will becomeapparent from the following description and the accompanying drawings,in which:

FIGURE 1 is a diagrammatic longitudinal section of a paper rewindingmachine incorporating the end sealing apparatus of the presentinvention.

FIGURE 2 is an enlarged diagrammatic longitudinal section of the endsealing apparatus of FIG. 1, parts thereof being shown in an alternativeoperative position.

FIGURE 3 is a fragmentary perspective of the transfer roll of the endsealing apparatus, showing how application of the bonding agent to thesheet material according to a particular pattern is achieved.

FIGURE 4 is a diagram of the pneumatic and electrical circuits employedin the apparatus of FIGS. 1 and 2.

FIGURE 1 illustrates the end sealing unit ll) of this inventioninstalled upon a paper rewinding machine 12 of the type described indetail in the application of T. M. Turner et al., Ser. No. 845,415,owned by the same assignee as the present application. In this machine12, the paper to be'wound into market size rolls passes from a rotatablysupported, mill-size, parent or supply roll 14 around a guide roll 16 inthe form of a continuous web 18. The Width of this web is a multiple ofthe axial length of a standard market size roll and the rewindingmachine 12 winds the web 18 into a lon roll corresponding in diameter tothat of the desired market size rolls. These long rewound rolls areknown as logs and are subsequently cut into several short rolls of thedesired length. It is to be understood, however, that the end sealingunit of the present invention is not limited in its adaptability towinders of this character but can be used with equal advantage withwinders provided with slitting knives that cut the web longitudinallyinto strips so that a plurality of rolls, each of standard market size,are formed simultaneously and do not require subsequent separation fromeach other. Nevertheless, for the sake of convenience in the presentdisclosure, the product of the rewinding machine 12 will hereinafter bereferred to as logs of sheet material wound upon itself into a roll.

In the illustrated rewinding machine 12, the web 18 passes from theguide roll 16 onto and around a knife carrying drum iii, the severalknives 22 of which are formed with serrated cutting edges adapted toregister with axially extending grooves 26 in the peripheral surface ofan anvil roll 28 which makes rolling engagement with a region of the Web18 which is in contact with the drum 20. Thus, the drum 26, knives 22,and grooved anvil roll 28 cooperate to transversely perforate the web 18in conformity with common practice, tode lineate individual sheets ineach of the rewound rolls and to facilitate separation of selectedlengths of paper therefrom.

From the perforating drum and anvil roll 28 the web 18 passeshorizontally to a bed roll 30 and around approximately a quarter of itscircumference where it reaches a winding mechanism indicated in itsentirety at 32. Here the web 18 is applied to and wound upon cores 34carried successively downward past the bed roll 30 by a pair of opposed,constantly advancing chains 36 (one shown in FIG. 1). Since the detailsof construction and the manner of operation of the winding mechanism 32do not constitute part of the present invention, it will suffice for thepurposes for present disclosure to explain that by the time a sufficientlength of the web 18 has been wound upon a core 34 so that the log 38has attained the desired size, the chains 36 will have carried the log38 past a breaker bar 40 which is mounted on a shaft 42 forreciprocatory pivotal movement through the plane occupied by the part ofthe web 18 which extends from the bed roll 30 to the fully wound log 38.At this time the breaker bar 40 is pivoted to the right as viewed inFIG. 1, causing the breaker bar 40 to engage and eflect severance of thecompleted log 33 from the remainder of the web 18 and to apply the newlyformed end of the web 1% to the next successive core 34 and thuscommence winding another log 38. The means for actuating the breaker bar40 includes a cam follower roller 44 rotatably mounted upon a bracket 46rigid with the breaker bar 40, and a cam 48 carried by a shaft 50 whichis driven in timed relation with the winding mechanism 32 so as torapidly actuate the breaker bar 40 each time the winding of a log 38 iscompleted, all as fully explained in the above identified Turner et al.application, Ser. No. 845,415.

The guide roll 16, knife carrying drum 20, anvil roll 28, bed roll 30,and cam shaft 50 are journalled at or adjacent their ends in the frame52 of the winding machine 12, and any convenient means may be employedfor causing the web 18 to feed through the winder 12, such as a powerdrive (not shown) operably coupled to any or all of the rolls 16, 28 and30 and the drum 20 to cause them to rotate at the same peripheral speed.

The function of the end sealing unit 10 of the present invention is tocause the end of the web 18 which has been wound onto each core 34 to bebonded to the immediately underlying layer of the web, thus to preventthe completed logs 38 from unwinding and thus developing loose ends ortails which would interfere with subsequent in-plant handling of thelogs and would impair their market value, as hereinabove explained. Inorder to accomplish this function the end sealing unit 10 comprises amechanism for applying a quantity of thermoplastic material to a regionof the web which is just about to reach a log being wound, suchapplication of the material occurring at a time immediately before thebreaker bar 40 causes severance of the completed log from the parent web18.

As is more clearly shown in FIG. 2, the mechanism 60 for applyingthermoplastic material to the web comprises a hopper 62 for storing asupply of dry, powdered thermoplastic material. The hopper 62 is mountedin any convenient manner on the frame 52 above the horizontal section ofthe web extending from the drum 20 to the bed roll 30. All or part ofthe top wall of the hopper 62 is attached to the body of the hopper byone or more hinges 64, to provide a cover which may be opened to permitloading the hopper with the powdered thermoplastic material.

The otherwise open bottom of the hopper 62 is closed by a transfer roll66 rigidly secured to a shaft 68 which is journalled at or adjacent itsends in the ends of the hopper 62. This roll 66 substantiallycorresponds in length to the width of the web 18. The shaft 68 andtransfer roll 66 are so related to the hopper 62 that the upperapproximately one third of the roll 66 is exposed to the powderedmaterial within the hopper while the lower part is outside the hopper,as shown in FIGS. 1 and 2.

Also rigidly secured to the shaft 68 adjacent one end thereof is a lever70, and a piston rod 72 is pivoted to the outer end of the lever 70 by apin 74. The piston (not shown) associated with the piston rod 72 isreciprocable within a double acting pneumatic cylinder 76 which ispivoted by a pin 78 to a bracket 80 rigidly mounted on the frame 52 ofthe winder 12. The parts are so proportioned and arranged that when airunder pressure is supplied to a tube 82 at one end of the cylinder 76and a tube 84 at the other end of the cylinder is vented to atmosphere,the piston rod 72 is moved so as to rotate the transfer roll 66 in acounterclockwise direction as viewed in FIGS. 1 and 2, far enough tomove the knurled areas out of the hopper. Conversely when the tube 82 isvented to atmosphere and air under pressure is supplied to the tube 84,the piston rod 72 is retracted into the cylinder 76, turning thetransfer roll 66 to the same extent and in the opposite direction.

Areas 86 of knurling (FIGS. 2 and 3) on the circumferential surface ofthe transfer roll 66 are arranged in groups 88 which extend in astraight line longitudinally of the roll. One such group of knurledareas 86 is provided for each part of the web 18 that is to comprise asingle marketable size roll, and there are three knurled areas 86 ineach group 88 on the roll 66 of the particular exemplary sealing unit 10illustrated. Whereas the knurled areas 86 are somewhat narrow measuredparallel to the axis of the roll 66, they are considerably longermeasured circumferentially of the roll, extending around approximately aquarter of the rolls circumference. They are so related to the lever 70that when the piston rod 72 is fully extended the knurled areas 86 aresubstantially entirely within the hopper 62, as shown in FIG. 1, andwhen the piston rod 72 is fully retracted the knurled areas are outsidethe hopper, as shown in FIG. 2. Consequently each of the knurled areasreceives a small quantity of the powdered thermoplastic material and,when the piston rod 72 is retracted, carries its charge of thermoplasticmaterial to the outside of the hopper.

A Wiper blade 90 is fastened to the lower edge of a side wall 92 of thehopper 62 in position to make sliding, or wiping engagement with theroll 66 and thus defines one edge of the opening through which the roll66 extends into the interior of the hopper 62. The wiper blade 90,therefore, prevents the powdered material from being carried from thehopper 62 by any parts of the transfer roll 66 except the knurled areas86. A second wiper blade 94 is attached to the opposite side wall 96 inposition to slidably engage the transfer roll 66 along the opposite edgeof the hopper opening through which the transfer roll 66 extends. Sincethe knurled areas 86 do not reach said second wiper blade 94 when thepiston rod 72 is fully extended, the blade 94 wipes the roll 66 cleanthroughout the full length of the roll and thus is effective to preventremoval of any significant quantity of the powdered material from thehopper when the roll 66 is turned in response to outward movement of thepiston rod.

An agitator roll 100 within the hopper 62 is mounted for rotation bymeans of a trunnion (not shown) on each end of the roll and journalledin a bearing (not shown) on the associated end of the hopper 62. One ofthe trunnions extends through the associated end of the hopper and isconnected by a sprocket and chain drive 102 (FIG. 1) to a gearhead motor104 (FIG. 1) whereby the agitator 100 is turned continuously. Thecircumference of the agitator roll 100 comprises a series of flats 106to each of which a wiper blade 108 is attached as by a row of screws 109(one shown for each blade 108). The wiper blades 108 are made ofresiliently flexible material and each extends throughout the fulllength of the roll 100, which substantially corresponds in length tothat of the transfer roll 66. The wiper blades are considerably widerthan the respective flats 106 and project substantially tangentiallyfrom the roll 100 in the counterclockwise direction as viewed in FIGS. 1and 2. The direction of rotation of the agitator roll 1% is clockwise asviewed in these figures and the roll 100 is positioned so close to thetransfer roll 66 that as the agitator 160 turns the blades 168 wipeacross a part of the circumference of the transfer roll 66.Consequently, the blades 1438 effectively impact or tamp powderedmaterial into the knurling of the transfer roll while the knurled areas86 are disposed within the hopper 62, thereby ensuring that when thetransfer roll 66 is subsequently turned to move the knurled areas 86 tothe outside of the hopper they will carry with them an effectivequantity of the powdered thermoplastic material.

The roll 1% and the blades 108 thereon also serve to agitate thepowdered material within the hopper 62 thus to prevent bridging of thatwhich remains within the hopper as the transfer roll removes the powderwithin the lower part of the hopper.

A cylindrical brush 111i is provided to whisk the powdered thermoplasticmaterial from the knurled areas 86 of the transfer roll 66 onto the web18. The cylindrical brush 110 is rigidly secured to a shaft 112 whichextends in parallelism with the transfer roll 66. The shaft 112 isjournalled adjacent its ends in two parallel arms 114 (one shown, FIGS.1 and 2) rigid with and depending from an elongate sleeve 116 which isrotatable upon a shaft 118 extending across the rewinding machine 12 andmade fast at its ends to the machine frame 52. Consequently the twobrush carrying arms 114 are rigidly interconnected and the applicatorbrush 110 can be swung toward and away from the transfer rolls 66 byturning the sleeve 116 upon the stationary shaft 118..

This is accomplished by means of a double acting pneumatic cylinder 12%(FIGS. 1, 2 and 3) whose piston rod 122 is pivoted by a pin 124 to theupper end of a lever 126 rigid with the sleeve 116 and projecting upwardtherefrom. For convenience of manufacture the lever 126 may be an upwardextension of one of the brush carrying arms 114 as illustrated in FIGS.1 and 2.

The cylinder 120 is pivotally mounted as by a pin 12S upon a bracket 13%rigid with the machine frame 52 and it and its piston rod 122 are sorelated to the lever 126 and the arms 114 carrying the applicator brush110 that when the piston rod 122 is retracted into the cylinder 12% thebrush 111 is swung toward the transfer roll 66 far enough for itsbristles to engage the surface thereof, as illustrated in FIG. 2.Retraction of the piston rod 122 into the cylinder 129 to effect suchengagement of the brush 116 with the transfer roll 66 is accomplished bysupplying air under pressure to a tube 132 at one end of the cylinder121i and by venting to atmosphere by a similar tube 134- whichcommunicates with the opposite end of the cylinder. Conversely, when airunder pressure is applied to the tube 134 and the tube 132 is vented toatmosphere the piston rod 122 is pushed to the left as viewed in FIG. 2,to effect withdrawal of the brush 116 from its engagement with thetransfer roll 66, as shown in FIG. 1.

Means are provided for rotating the cylindrical brush 110counterclockwise as viewed in FIGS. 1 and 2 so that the bristles of thebrush engaging the transfer roll 66 at any time move downward toward thehorizontal portion of the web 13 approaching the bedroll 30. Asindicated in FIG. 1 this driving means conveniently comprises arelatively large driving gear 140 rigidly connected to the bed roll 3%in coaxial relation therewith and a smaller, driven gear 142 enmeshedwith the driving gear 140 and rigidly mounted upon the shaft 112 of thecylindrical brush 110. Consequently, at all times when the rewindingmachine 12 is in operation the cylindrical brush 110 is rotated at arelatively rapid rate in the, direction which causes the bristles on theside closest to the transfer roll 66 to be moving downward toward 6 thehorizontal portion of the web 18 which is approaching the bed roll 30.

A pair of brackets 150 (one shown in FIGS. 1 and 2) are rigidly clampedto the sleeve 116 for rotary motion therewith about the axis of thestationary shaft 118. Consequently, these brackets 15%) move similarlyto and simultaneously with the arms 114 which carry the cylindricalbrush 110. The lower ends of the brackets 150 are interconnected by arail 152 to the undersurface of which one flange of an angle bar 154 isrigidly attached. The other flange of the angle bar 154 carries a feltwiper 156 in such position that when the pneumatic cylinder 120 isactuated to move the brush toward the transfer roll 66 the wiper 156engages the web 18 ina region thereof which is engaged upon the bed roll30, as shown in FIG. 2. When the cylinder is oppositely actuated,however, the wiper 156 is moved out of engagement with the web 18, asshown in FIG. 1.

It has been found that under certain circumstances the felt wiper 156may be replaced by a rotatably mounted, rubber covered roll whichoperates continuously to force the powder into the web.

The mechanism for operating the cylinders 76 and 120 in timed relationwith operation of the rewinding machine 12 is diagrammaticallyillustrated in FIGS. 1 and 4. It comprises a four Way air valve 166whose two delivery ports are connected to the tubes 82 and 84,respectively, of the cylinder 76 which actuates the transfer roll 66,and a second four way air valve 162 whose two delivery ports areconnected with the tubes 132 and 134, respectively, of the cylinder 12%which effects movement of the cylindrical brush 110. The supply ports ofboth of the valves 16% and162 communicate with a source of air underpressure as indicated at 164.

The valves 160 and 162 are actuatedby solenoids166 and 168,respectively. The parts are so arranged that y when the solenoid 166 isenergized the valve 160 comnects the tube 84 of the cylinder '76 withthe air supply 164- and connects the tube 82 at the opposite end of thecylinder '76 with a port which leads to the atmosphere. Thus,energization of the solenoid 166 effects retraction of the piston rod 72and thereby causes the 7 transfer :011 66 to rotate clockwise asviewedin FIGS.

1 and 2, far enough to turn the row of knurled areas 86 out of thehopper 62 and into the path of the cylindrical brush 110. When thesolenoid 166 is deenergized the core (not shown) of the valve 161) isreturned by a spring 4 (not shown) to the position wherein the airsupply 164 material.

When the solenoid 168 is energized it actuates the valve 162 to connectthe air supply 164 with the tube 132 of the cylinder 120 to retract thepiston rod 122 and to connect the tube 134 at the opposite end of thecylinder 120 to a venting port 174, and thereby effects movement of therotating cylindrical brush 119 toward the transfer roll 66. Upondeenergization of the solenoid 168 the core (not shown) of the valve 162is returned to the position wherein the air supply 164 is connected tothe tube 134 while the tube 132 is connected to a second venting port175, thus to effect withdrawal of the cylindrical brush 116 to theposition illustrated in FIG. 1.

The solenoids 166 and 168 are controlled by microswitches 176 and 178,respectively, which are operated in rapid succession by means of a cam186 secured to the same shaft 513 as that which carries the breaker baractuating cam 48. As above explained, this shaft 56 makes one completerevolution for each log 38 completed by the Iewinding machine 12. Sincethe microswitch 178, the microswitch 176 and the breaker bar 140 shouldbe operated in rapid succession in that order, a very brief intervalbefore completion of a log,-the shaft 50 is operated by means of asingle revolution clutch (not shown) to make one complete revolutionvery rapidly at the proper time in the cycle of operation in therewinding machine. This type of drive for the mechanism that operates tosever a completed log from the parent stock is well known and need notbe explained in detail herein. For a complete explanation of a suitablemechanism for causing the cam shaft 56 to make one complete revolutionat a relatively high rate of speed just before the winding of a log 38is completed reference may be had to United States Patent No. 2,883,121,issued April 21, 1959, to N. S. Barlament, which discloses a cam shaftcorresponding to the cam shaft 50 and driven by a single revolutionclutch to rapidly make one full turn and thereby effect separation of acompleted rewound roll from the parent sheet stock.

Means are provided for applying heat to each completed log 38 so as tomomentarily make tacky, or sticky, the powdered thermoplastic materialthat was applied to the web 18 just prior to completion of the log. Ashaft 190 (FIG. 1) extending transversely of the rewinding machine 12 isjournalled adjacent its ends in the frame 52. A pair of arms 192 (oneshown, FIG. 1) are rigidly attached to the shaft 190 so that the twoarms remain parallel to each other. The two arms 192 rotatably support aroller 194 whose length is at least as great as the logs 38 wound by themachine 12. An electrically energized heating element 196 is providedinside the roller 194 to maintain the temperature of the roller 194sufiiciently high to make tacky the powdered thermoplastic materialapplied to the terminal portion of the sheet material of each log 38. Inas much as conventional means are employed for connecting the heatingelement 196 to a source of electrical energy it need not be describedherein.

The shaft 190 is so situated and the arms 192 are of such length thatthe heated roll 194 is adapted to engage for a brief period each of thecompleted rolls after it has been carried by the chains 36 beyond therange of operation of the breaker bar 40. The heated roll 194 is pressedagainst the successive completed rolls 38 by means of a spring 198 undertension between a suitable frame part 200 and a lever arm 202 rigid withand projecting downward from the shaft 190.

The heated roll 194 is constantly rotated by means of a. gearhead motor210 whose output shaft 212 carries a sprocket 213 connected by a chain214 to a sprocket 216 which is rotatable upon the shaft 190. Anothersprocket (not shown) likewise mounted for rotation upon the shaft 190and rigidly connected to the sprocket 216 is connected by another chain218 with a driven sprocket (not shown) coaxial with and rigidly attachedto the heated roll 194.

The manner in which the above described apparatus operates to performthe method of the present invention is as follows:

It will be assumed that the rewinding machine 12 is in operation torewind successive rolls 38 in a manner fully explained in the aforesaidTurner et al. application, Ser. No. 845,415. A very brief intervalbefore completion of one of the logs 38 the cam 180 closes the switch178 and immediately thereafter the switch 176. Therefore, the cylinder120 is first actuated to retract its piston rod 122 and thus swing thecylindrical brush 110 to the left as viewed in FIGS. 1 and 2, so thatits downwardly moving bristles sweep the adjacent portion of thecircumference of the transfer roll 66.

Immediately thereafter the cylinder 76 is actuated to retract its pistonrod 72 and thereby turn the transfer roll 66 clockwise and thus topresent the knurled areas 86 of the roll 66 to the rotation brush 110.

Each of the knurled areas 86 carries a charge of the powderedthermoplastic material which it acquired while it was within the hopper62, retention of the material within the knurling until it is presentedto the brush 110 being assured by the fact that the wiper blades 188 ofthe agitator roll tamp the powdered material into the knurling prior toactuation of the cylinder 76. Consequently, as the transfer roll 68turns its knurled regions 86 into engagement with the bristles of therotating brush the powdered material is whisked downward by the rotatingbrush and is thus deposited upon the horizontal portion of the web 18which is approaching the bed roll 30.

Because of the arrangement of the knurled areas 86 in groups 88 as abovedescribed and as illustrated in FIG. 3, the powdered material isdeposited in fairly well defined similarly grouped areas 220 upon theupper surface of the rapidly advancing web 18 and as the web progressesaround the bed roll 30 the material thus deposited is worked into theweb 18 by the wiper 156' so as to prevent dislodgement of the powderedmaterial from the web as the coated areas 220 approach and are woundonto the log 38 being completed.

The cam 48 which operates the breaker bar 40 and the cam 189 whichoperates the microswitches 176 and 178 are so related to each other thatalthough the web 18 is advancing very rapidly, the breaker bar 48 isactuated after the coated areas 220 have passed the range of operationof the breaker bar 40 but before a length of the web 18 corresponding tothe circumference of a completed roll 38 and following the coated areas220 has passed the breaker bar 40. Consequently, when a roll 38 iscompleted the coated areas 220 occur on the under or inner surface ofthe outermost layer of sheet material which has been wound upon itselfto form a log 38, and when the thus completed log 38 is carried by thecontinuously advancing chains 36 into engagement with the heated roller194 the thermoplastic material will be melted, or at least softened, tothe extent that it becomes tacky so that said outermost layer of thesheet material will be bonded to the immediately underlying layer. Inthis manner after the completed rolls 38 have been discharged from therewinding machine 12 they are effectively secured against unwinding toany material extent.

It is desirable, however, that the earns 48 and 180 be so related toeach other that a short length of the web 18 following the coated areas220 shall pass the breaker bar 40 before the breaker bar is actuated tosever the log being completed from the parent web 18, thus leaving thelast inch or so of the sheet material unattached to the roll to act as apull tab to facilitate commencement of unwinding of the roll when it isplaced in use. This manner of operating the machine is not mandatory,however, since the breaker bar may operate into a coated area of theweb. In this case the coated area may be relatively wide, thus assuringthat the end of the rolled sheet or strip will be bonded to the rolleven if the web does not break along the line of perforation closest tothe breaker bar.

It is also to be understood that the turning movement of the transferroll 66 may be always in the same direction, this being accomplished bymeans of a ratchet mechanism or one way clutch connecting the lever 70to the transfer roll 66. Since such drive mechanisms and their manner ofinstallation are well known, they need not be described in detailherein. If such intermittent, one way rotation of the transfer roll isadopted, the knurled areas 86 may be in the form of continuous bands ofknurling, extending throughout the full circumference of the transferroll. Furthermore, the knurling may be continuous throughout the fulllength of the transfer roll 66, in which case the powdered material Willbe applied according to a pattern which is continuous acrosssubstantially the full width of the web.

Whereas various powdered thermoplastic materials are available and havebeen found satisfactory for use in the performance of the presentinvention, one such material which has been found to beentirelysatisfactory for the purpose is powdered polyethylene for the reasonsthat it forms a dependably satisfactory bond between the outermost layerof the sheet material in the completed roll and 9 the immediatelyunderlying layer and does not stain or otherwise injure the sheetmaterial. Furthermore, it is dry, non-toxic, and, for all practicalpurposes, inert.

Whereas a particular embodiment of the present invention has been shownand described, it will be understood that various changes may be made inthe details thereof without departing from the scope of the invention asdefined from the appended claims.

Having thus described the invention, What is believed to be new and isdesired to be protected by Letters Patent is:

1. The method of forming a succession of scaled rolls of paper from acontinuous strip of the paper, which comprises securing the strip to afirst core, rotating the core to wind the strip thereupon to form thestrip into a first roll, applying particles of powdered polyethylenematerial to said strip in an area approaching the roll, attaching aregion of the strip farther from said roll than said area having thepolyethylene material thereupon to another core, severing said stripbetween said attached region and said area having the polyethylenethereupon, continuing rotation of said first core to accumulate saidarea having the polyethylene material thereon into said first roll,applying heat to said first roll to make the polyethylene material tackyand thereby bond said area to the underlying layer of the paper Withinsaid first roll, and rotating said second core to form a second roll ofthe paper thereupon.

2. Paper roll forming apparatus comprising means for supplying a stripof paper, core means for winding said strip of paper into a roll, meansmounted adjacent said winding means for depositing a quantity ofthermoplastic material upon a selected part of said strip, means forsevering said strip, means for operating said strip severing means afterthe selected part of the strip bearing the thermoplastic material and anadditional length of the strip has passed said strip severing means, andmeans for heating said thermoplastic material when it has been wound onsaid core means for simultaneously bonding said selected part of thestrip to the underlying strip portion on said core means and causing thetail end of the strip to provide a pull tab.

3. Paper converting apparatus comprising means for supplying acontinuous strip of paper, means for Winding said strip of paper uponitself to form it into a roll, means mounted adjacent said strip betweenthe supplying means and said winding means for depositing a quantity ofthermoplastic material upon a selected part of said strip approachingthe winding means, means for severing the strip adjacent said selectedpart and beyond the same from the winding means, and means for heatingthe formed roll after said selected part has been accumulated by thewinding means to render said thermoplastic material tacky and therebybond said selected area to an adjacent layer of the roll.

4. In a roll sealing mechanism for a machine for advancing a strip ofsheet material along a predetermined path and Winding it upon itselfinto a roll, the combination of a hopper for storing a supply ofpowdered heat sensitive adhesive, transfer means movably mountedadjacent said hopper and projecting thereinto to receive upon a surfacethereof a charge of said powdered adhesive, applicator means mountedadjacent the path of movement of said strip of sheet material and inposition to engage said transfer means, means for moving the transfermeans to withdraw said surface thereof from within the hopper into therange of operation of the applicator means, and means for actuating saidapplicator means to cause it to move the powdered adhesive from thetransfer means onto an area of said strip of sheet material as it passessaid hopper.

5. in a roll sealing mechanism for a machine for advancing a strip ofsheet material along a predetermined path and winding it into a roll,the combination of a hopper for storing a supply of powdered heatsensitive adhesive, transfer means movably mounted adjacent said ithopper and projecting thereinto to receive upon a predetermined partthereof a charge of said powdered adhesive, hrush means movably mountedadjacent the path of movement of said strip of sheet material and inposition to engage said trans-fer means, and means for moving thetransfer. means to advance said predetermined part thereof from withinthe hopper into engagement with said brush means, and means foractuating said blush means to cause it to whisk the charge of powderedadhesive from the transfer means onto an area of said strip of sheetmaterial as it passes said transfer means.

6. In a roll sealing mechanism for a machine for advancing a strip ofsheetmateria-l along a predetermined path arid winding it into a roll,the combination of a hopper for storing a supply of powdered heatsensitive adhesive, movahly mounted transfer means having 'a knurledarea and projecting through an aperture in a wall of the hopper toexpose said knurled area thereof to said powdered adhesive, acylindrical brush rotatably mounted adjacent the path of movement ofsaid strip of sheetmaterial and in position to engage said transfermeans, means for moving the transfer means to advance said knurled areathereof from within the hopper into engagement with said brush, andmeans for rotating said brush in the direction causing it to whisk thepowdered adhesive from the transfer means onto an area of said strip ofsheet material as it passes said transfer means.

' 7. In a roll sealing mechanism for a machine for advancing a strip ofsheet material along a predetermined path and winding it into a roll,the combination of a hopper for storing a supply of powdered heatsensitive adhesive, movably mounted transfer means having a knurled areaand projecting through an aperture in a wall of the hopper to exposesaid knurled area thereof to said powdered adhesive, a cylindrical'brush mounted for rotation and for movement into and out of engagementwith said transfer means at a position adjacent the path of said stripof material, means for moving said brush into engagement with saidtransfer means, means operable subsequently to operation of said brushmoving means for moving said transfer means to advance said knurled areathereof from within the hopper into engagement with the brush, means forrotating said brush in the direction causing it to whisk the powderedadhesive from the transfer means onto an area of said strip of sheetmaterial as it moves along said path adjacent said brush.

8. In a roll sealing mechanism for a machine for advancing a continuousstrip of sheet material along a predetermined path and winding it into aroll, the combination of a hopper for storing a supply of powdered heatsensitive adhesive, a knurled transfer roll rotatably mounted adjacentsaid hopper and adjacent the path of said strip material and projectingthrough an aperture in a Wall thereof to expose a part of its knurledsurface to said powdered adhesive, means operable within the hopper forpressing the powdered adhesive into the depressions of said knurledsurface, means for turning the transfer roll to advance a region of itsknurled surface from within the hopper to a position adjacent the stripof material, a cylindrical brush rotatably mounted adjacent said stripof sheet material and in position to engage the knurled surface of saidtransfer roll, means for rotating said brush in the direction causing itto sweep the powdered adhesive from the transfer roll onto an area ofsaid strip of sheet material.

9. In a method of forming secondary rolls of sheet material ofpredetermined lengths from a primary roll which defines the source ofsuch sheet material wherein the trailing end of such lengths are joinedsolely to the adjacent layer of the secondary rolls respectively, theimprovement comprising the steps of irnbedding powdered thermoplasticmaterial in a predetermined portion of the sheet, severing the sheet ata part longitudinally spaced from such predetermined portion, windingthe resulting trailing end on the secondary roll, establishing contactbetween the powdered thermoplastic material and the inwardly adjacentlayer of sheet material, and heating the trailing end to render thethermoplastic material tacky and thereby bond the trailing end to theinwardly adjacent layer.

10. The method of claim 9 wherein the imbedded thermoplastic material iseffective to become bonded only to the inwardly adjacent layer of thesecondary roll.

11. The method of claim 9 wherein imbedding the thermoplastic materialto the predetermined portion is caused *by training the sheet past aflexible member that is in frictional engagement therewith to therebyforce the powdered material into the pores of the sheet.

12. The method of claim 9 further comprising supporting the surface ofthe sheet that is opposite the predetermined portion to which thethermoplastic material is located, and simultaneously etfecting saidimbedding by forcing the thermoplastic material into the pores of thesheet.

13. Paper converting apparatus comprising means for supplying acontinuous strip of paper, means for winding said strip of paper uponitself to form it into a roll, means mounted adjacent said strip betweenthe supplying means and said winding means for depositing a quantity ofCir thermoplastic material upon a selected part of said stripapproaching the winding means, means for applying pressure to thethermoplastic material to urge it into intimate contact with the surfaceof the paper, means for severing the strip adjacent said selected partand beyond the same from the winding means, and means for heating theformed roll after said selected part has been accumulated by the windingmeans to render said thermoplastic material tacky and thereby bond saidselected area to an adjacent layer of the roll.

References Cited in the file of this patent UNITED STATES PATENTS533,305 Lee Jan. 29, 1895 981,129 Seigle Jan. 10, 1911 2,050,794Humphner Aug. 11, 1936 2,298,004 Fisher et a1. Oct. 6, 1942 2,507,144Christman May 9, 1950 FOREIGN PATENTS 117,104 Australia June 8, 1943

13. PAPER CONVERTING APPARATUS COMPRISING MEANS FOR SUPPLYING ACONTINUOUS STRIP OF PAPER, MEANS FOR WINDING SAID STRIP OF PAPER UPONITSELF TO FORM IT INTO A ROLL, MEANS MOUNTED ADJACENT SAID STRIP BETWEENTHE SUPPLYING MEANS AND SAID WINDING MEANS FOR DEPOSITIING A QUALITY OFTHERMOPLASTIC MATERIAL UPON A SELECTED PART OF SAID STRIP APPROACHINGTHE WINDING MEANS, MEANS FOR APPLYING PRESSURE TO THE THERMOPLASTICMATERIAL TO URGE IT INTO INTIMATE